1. Field of the Invention
This invention pertains generally to viewers or viewing devices and, more particularly, to viewing devices having reflectors therein.
2. Description of the Related Art
Optically variable devices are disclosed in U.S. Pat. Nos. 4,705,300 and 4,705,356. Optically variable devices which can be used in optically variable inks and optically variable pigments are disclosed in U.S. Pat. Nos. 5,171,363 and 5,279,657. The color shift characteristics of these devices and inks can be used for currency authentication. Relative movement between the observer and the optically variable device is typically needed to visualize these color shifts. There is a need for a viewing device which can be used by an observer to confirm the authenticity of an optically variable device without the need of relative movement between the observer, the optically variable device or the viewing device.
In general, it is an object of the present invention to provide a viewing device which permits an observer to quickly confirm the color shift characteristics of an optically variable device.
Another object of the invention is to provide a viewing device of the above character which permits the observer to simultaneously view two discrete colors reflected by an optically variable device.
Another object of the invention is to provide a viewing device of the above character in which the confirmation of authenticity of an optically variable device is reproducible.
Additional objects and features of the invention will appear from the following description from which the preferred embodiments are set forth in detail in conjunction with the accompanying drawings.